The cryptographic signature guarantees the file is safe to install and was not tampered
with in any way.

This release does not have a Play Store Description, so we grabbed one from version 4.8.1:

KingRoot is a root tool for "lazy people" who just want to get root access but don't want to flash any third party Recovery into their lovely device. It can work on almost all device from Android 2.x – 5.0. Working of KingRoot based on system exploit. The most suitable Root strategy will be deployed from cloud to your device according to your ROM information. So, it’s necessary to keep net connection during root process. What’s more, KingRoot(app) will not trip Samsung KNOX and have ability to close Sony_RIC perfectly. Meanwhile, unroot operation also can be done easily by just click the button in the menu of KingRoot. PURIFY is an optimized tool for your Android OS. She can help you to save battery power, improve device standby time, increase speed and return your device to it's pure state. PURIFY works only with ROOT access so if your device is not rooted, you must obtain it before using PURIFY. You can obtain ROOT access through KingRoot . First and foremost, the first thing we can do is extend standby time and save your battery power. Through purifying apps that insist on running in the background, we can save RAM for you and let your device run faster than ever! Moreover, for the applications that utilize larger than average amounts of RAM, these too can also run smoothly after purifying mode is implemented. PURIFY can also help you archive notifications and give you a clean notification bar.